All of the projects described in this Program Project either require a constant and consistent supply of uterine artery endothelial cell (UAEC), ovine placental artery endothelial cells (OFPAEC) (Projects I and II) or use these cells and HUVEC-C (immortalized cells from ATCC) cells in the Core laboratory for mitogenic assays (Projects I, III, and IV). The role of the core is to not only relieve the project personnel of the burden of preparing frozen stocks of these cells, but also to provide a high quality of cell preparation and to provide uniformity of data acquisition between the projects. This core will also undertake to determine NO levels as well as bFGF and VEGF levels in human trophoblast culture media from experiments performed, so again improving overall productivity and providing consistency of analysis. In addition, this core will evaluate changes in human placental vascular density as proposed in Projects III and IV. In this way comparison of data between projects can be maximized to the full. Thus our specific aims are and the projects which will utilize this core are: Aim 1: Preparation and distribution of OFPAEC and UAEC frozen stocks for Projects I, III, and IV. Aim 2: Maintenance and distribution of HUVEC-C as required mainly for Project III but also Project I and II when the need arises. Aim 3: Performance of Mitogenesis and Migration assays of treatments or conditioned medium using OFPAEC, UAEC and confirmed using HUVEC-C as the human equivalent (Project III and IV). Aim 4: Measurement of NO in experimental media (Projects I, II, III, IV). Aim 5: Measurement of bFGF and VEGF by ELISA in experimental media to confirm immunohistochemistry data (Projects I-IV). Aim 6: Measurement of cell proliferation index by immunohistochemistry (PCNA/Ki67) and vascular density by Volumetric Morphometry Analysis (Project IV). Aim 7: Provide backup services for storage of essential resources (cells, conditioned media, and immunohistochemistry) and provide an available source of fresh reagents which have short half life or are significantly more economical when purchased in bulk.